Seismic active earth pressures on rigid retaining walls under RT mode considering rotation of principal stresses

Considering the rotation of the principal stresses, new formulae for seismic active pressures on rigid retaining walls under rotation about top (RT mode) are derived by the pseudo-static method. Through the rotation model, the calculation of seismic active earth pressures by the pseudo-static method is transforming into that of static active earth pressures, and the seismic active rupture angle is obtained by means of the Coulomb earth pressure theory. According to the Mohr stress circle and the improved circular arc trajectory of the minor principal stresses being a circular arch, the coefficients of the lateral seismic active earth pressures and the horizontal interfacial frictions are proposed under RT mode. Then based on the force equilibrium of the differential sliding backfill element, the formula for the seismic active earth pressures on the rigid retaining wall under rotation about top is obtained. Moreover, the effects of influence parameters on the seismic active rupture angle, lateral seismic active earth pressure and its coefficient, horizontal interfacial friction coefficient, resultant of the seismic active earth pressure and height of its application are discussed. And comparisons of the predicted values by the proposed method and other methods are carried out as well as model tests, and it is shown that the proposed method is more reasonable and effective than other methods.